Upstage
•
Solar Decide Flash
•
Released 
October 2026

Upstage
Solar Decide Flash

Upstage's low-latency decision model that returns typed choices, scores, and probabilities instead of text, for routing and policy checks.

Modality:
Text
model ID
upstage/solar-decide-flash

Output Speed *

N/A
tok/s

Intelligence Index *

N/A
/ 100

Context Window *

524288
tokens

Input price

0.3
Anytoken

Output price

0
Anytoken
Solar Decide Flash: Typed Decisions With Probabilities, Built for Low Latency Solar Decide Flash is Upstage's low-latency structured decision model, a faster variant of Solar Decide built on Solar Mini 4. It does not write prose. It reads a state, such as a ticket or a full document, and answers typed questions with a choice, a score, or a yes/no probability. It suits routing, classification, and policy checks in the hot path of an application, especially Korean-language content. Access Solar Decide Flash via AnyAPI.ai

Performance

Why One Forward Pass Per Decision Matters for Gating Latency

Solar Decide Flash is tuned for consistently fast response times in routing, classification, and policy checks. Upstage says each decision takes a single forward pass because the model generates no text. Output tokens are not billed. It keeps a 524,288-token context window, so long documents can be the state. This design removes variable-length generation from the request path. We found no independent latency measurements for Flash, so test time to first response on your own traffic. It is best used as a fast gate in front of heavier models.

Technical Specifications

What the model supports

Solar Decide Flash accepts text and returns structured decisions, not generated prose. It has a 524,288-token context window. Maximum output length is not a meaningful limit, because answers are choices, scores, or yes/no probabilities, each with a probability from the model. The long context is the specification with the biggest production impact. It lets an entire contract, ticket thread, or document be the state. It does not make the model a chat endpoint, and chat SDKs will not call it.
Verified Specifications — 
Solar Decide Flash
*
Input modalities
Text
output modalities
Text
Context window
524288
 tokens
Maximum output tokens
471859
Reasoning
No
Knowledge cutoff
October 2026
Pricing (standard)
0.3
 AnyTokens in
 / 
0
 AnyTokens out

Comparison

Solar Decide Flash or Solar Decide: Which Decision Model to Deploy?

Solar Decide is the direct sibling. Upstage describes Flash as a faster variant of Solar Decide. Both are built on Solar Mini 4 and use the same typed-question System One approach. Both return choices, scores, or yes/no answers with probabilities in a single forward pass, and both offer a 512K context. OpenRouter lists them at the same input rate with free output. The decision is whether Flash's latency tuning outweighs the more established model.

Dimension
Solar Decide Flash
Solar Decide
Context window *
524288
tokens
524288
tokens
Output speed *
N/A
tok/s
N/A
tok/s
Intelligence Index *
N/A
N/A
Input pricing
0.3
AnyToken
0.3
AnyToken
Output pricing
0
AnyToken
0
AnyToken
Knowledge cutoff *
October 2026
September 2026

Choose Solar Decide Flash when decisions sit in a user-facing or high-volume path, such as routing, moderation, or policy gating, and consistent response time matters most. Choose Solar Decide when latency is secondary, or when you want the model Upstage's own System One reference documents as available. Neither has published accuracy benchmarks that we could find, so run both on your labeled examples and compare calibration before committing.

Limitations & Trade-offs

Where Solar Decide Flash falls short

1
No generated text. Solar Decide Flash returns typed decisions with probabilities and writes no prose. It cannot draft replies, explain its reasoning, summarize, or extract free-form text. That suits gating and classification, but any workflow needing language output must pair it with a generative model such as Solar Pro 4 or Solar Mini 4.
2
No published accuracy or speed benchmarks. Upstage published no benchmark for Solar Decide, and we found no independent accuracy, time-to-response, or throughput data for Flash. Latency tuning is an official claim, not a measurement. Label a few hundred real cases, set probability thresholds from that data, and send uncertain cases to a stronger check. This is editorial guidance, not a vendor claim.
3
Text-only input and a non-chat API shape. Flash accepts text, so images and scanned files need parsing first. It is served through the System One schema, so chat SDKs will not call it, and OpenRouter exposes decision models through an alpha Decisions API. Upstage's reference for Solar Decide caps a choice question at 26 options, so confirm that limit for Flash. Split larger taxonomies into several questions.
4
Thin first-party documentation. Upstage's System One reference lists only solar-decide as the available model name, and Flash appears through its OpenRouter listing, released October 8, 2026. Specifications such as maximum option counts and error behavior are documented for Solar Decide, so Flash-specific behavior should be tested before production rollout, especially for compliance-sensitive decisions.

Best-Fit Workloads

Where this model earns its place

01

Low-latency request routing

‍
Flash is tuned for consistently fast responses in routing, and each decision is one forward pass. It can pick a team, intent, or downstream model from a defined list of options. Probabilities support confidence thresholds, so low-confidence cases can escalate to a stronger model or a person. It is not suited to routing among more than the documented option cap in a single question.

02

Policy and moderation checks

‍
Yes/no questions return a probability, which fits policy checks such as urgency, sensitive content, or rule violations. Upstage positions the model for policy checks, and a 524,288-token context lets a whole document be the state. Thresholds should come from your labeled data, because no published accuracy data exists. Decisions that block customers or trigger payments should add human review.

03

Long-document classification

‍
A 524,288-token context window lets a full contract, report, or thread be classified or scored in one request, without chunking. Choice and score questions turn the document into labels and rubric positions with probabilities. This works well for triage and compliance screening. It will not extract or rewrite passages, since the model produces no text.

04

Korean-language triage

‍
Flash carries Solar Mini 4's Korean-language strength, per Upstage. It is a natural candidate for classifying and scoring Korean support tickets, messages, and documents. Upstage publishes no Korean benchmark for Flash, so validate on your own labeled data. Write option descriptions as short keywords and check results against your own category definitions.

Pricing in anytokens via AnyAPI
Input
0.3
₳
Output
0
₳
Cache write
0
₳
Cache read
0.3
₳

Integration

Access Solar Decide Flash via AnyAPI.ai

Access Solar Decide Flash through AnyAPI.ai using a unified API built for multi-model AI applications. Integrate Solar Decide Flash without maintaining a separate provider-specific connection, and keep the flexibility to test, switch, or combine models as your application requirements evolve.

01

One API integration

Access Solar Decide Flash and other AI models through the same API workflow instead of maintaining separate integrations for every provider.

02

Easy model switching

Test Solar Decide Flash against alternative models or switch models as your performance, capability, or cost requirements change without rebuilding your application around another provider API.

03

Flexible for production

Use Solar Decide Flash from experimentation through production while keeping your AI stack flexible as workloads, traffic, and model requirements evolve.

04

Multi-model applications

Use Solar Decide Flash for the workloads where it performs best and combine it with other models for tasks that require different capabilities, performance, or efficiency.

Frequently Asked Questions

Answers to common questions about integrating and using this AI model via AnyAPI.ai

Solar Decide Flash is Upstage's low-latency structured decision model, a faster variant of Solar Decide built on Solar Mini 4. It reads a text state and answers typed questions with a choice, a score, or a yes/no answer, each with a probability from the model. It was released on October 8, 2026.

No. Solar Decide Flash does not generate text. It returns typed decisions with probabilities and is served through Upstage's System One schema, not a chat-completions interface. Use a generative model such as Solar Pro 4 or Solar Mini 4 for conversation, summaries, or drafting, and use Flash to classify, route, or check inputs.

Solar Decide Flash has a 524,288-token (512K) context window, so a full document can serve as the state. Input is text only. There is no meaningful maximum output length in the generative sense, because responses are typed decisions rather than written text.

Upstage describes Flash as a faster, low-latency variant of Solar Decide. Both are built on Solar Mini 4, keep the 512K context window, and return typed decisions with probabilities. Flash is tuned for consistently fast response times in routing, classification, and policy checks. No published accuracy comparison exists, so test both on your own data.

Output tokens are not billed, so cost comes from input tokens, which makes it economical for high-volume gating. See the AnyTokens pricing component on this page for current rates. We found no published or independent benchmarks for Flash on accuracy or speed, so validate thresholds on labeled examples from your own workload.

* Benchmark data source: Artificial Analysis artificialanalysis.ai